Treatment barrel

ABSTRACT

Rotary barrel for treating materials, notably hides and skins, adapted to be rotated about an axis tilted to provide an upper bottom and a lower bottom shell, the barrel being rotatably supported by a pair of rollers and driven by one of these rollers, which are disposed adjacent the upper bottom for engagement with a race-forming annular ring rigid with the barrel, the lower end of the barrel being provided with a swivel bearing coaxial thereto. The barrel may have a cylindrical, biconical or cylindro-conical configuration, and be provided with internal pins, studs or bars of straight or helical profile for carrying along the materials to be treated, a drain cock being provided near the outer edge of the lower bottom, possibly with a discharge aperture formed in the wall of revolution adjacent to said drain cock, and a loading aperture formed in the free upper bottom shell, perforated plate means near the bottom inner corner for protecting the drain cock from clogging, and possibly an arrangement of helical ribs whereby rotating the barrel in one direction will perform the treatment while rotating same in the opposite direction will cause the treated materials to be discharged therefrom.

States Patent 91 France [22] Filed: Dec. 30, 1970 [21] Appl. No.: 102,601

[30] Foreign Application Priority Data April 1, 1970 France ..70l 1825 Dec. 4, 1970 France ..7044241 [52] U.S. Cl ..69/30 [51] Int; Cl ..Cl4c l/ [58] Field of Search ..69/30 [56] References Cited UNITED STATES PATENTS 3,664,161 /1972 Cressman ..69/ 3,665,735 5/1972 Brennan .69/30 3,518,849 7/1970 Egg'leston ..69/3O 820,021 5/1906 Smith ..69/3O 1,893,706 H1933 Kannel.... .....69/30 2,006,441 7/1935 Connor ..69/30 3,474,647 lO/l969 Dandliker ..69/30 Primary ExaminerAlfred R. Guest Attorney-Waters, Roditi, Schwartz & Nissen Pillard May 29, 1973 TREATMENT BARREL [57 ABSTRACT i 1 lnvemori Claude Pillard, y n, France Rotary barrel for treating materials, notably hides and [73] Assignefiz Centre Technique Du Cuir, Lyon skins, adapted to be rotated about an axis tilted to provide an upper bottom and a lower bottom shell, the barrel being rotatably supported by a pair of rollers and driven by one of these rollers, which are disposed adjacent the upper bottom for engagement with a race-forming annular ring rigid with the barrel, the lower end of the barrel being provided with a swivel bearing coaxial thereto. The barrel may have a cylindrical, biconical or cylindro-conical configuration, and be provided with internal pins, studs or bars of straight or helical profile for carrying along the materials to be treated, a drain cock being provided near the outer edge of the lower bottom, possibly with a discharge aperture formed in the wall of revolution adjacent to said drain cock, and a loading aperture formed in the free upper bottom shell, perforated plate means near the bottom inner corner for protecting the drain cock from clogging, and possibly an arrangement of helical ribs whereby rotating the barrel in one direction will perform the treatment while rotating same in the opposite direction will cause the treated materials to be discharged therefrom.

18 Claims, 6 Drawing Figures PAIENIED 3.735.611

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PAli-jmmzrxeems sum 3 OF 6 Fi c.3'

PATENT was I975 'snmsors BACKGROUND OF THE INVENTION The present invention relates to treatment barrels and has specific but not exclusive reference to a barrel for the treatment of hides and skins. In fact, specific steps in the treatment of hides by means of liquid and pulverulent products are performed either in tan liquor stirring apparatus or the like, or in rotary barrels revolving about a horizontal axis. Now hitherto known treatment barrels of this character are highly objectionable on account of their mode of operation which is neither homogeneous nor rational.

SUMMARY OF THE INVENTION It is the chief object of the present invention to avoid these inconveniences by providing a circular-sectioned rotary barrel characterized in that its pivotal axis merging into its axis of revolution is inclined to the horizontal, the angle of tilt being subordinate to the nature of the treatment to be performed and also to the quality and nature of the materials to be treated.

With this arrangement the hides or skins and the treatment liquids and/or powders are thoroughly mixed.

According to a first form of embodiment of the present invention, the barrel is of substantially cylindrical configuration and comprises on its external surface, near its upper end, an annular member or ring through which the barrel bears by gravity on a pair of rollers having their axes parallel to the barrel axis, said ring acting as a race to said rollers, the opposite end of the barrel being provided with an axial stub shaft journaled in a swivel bearing also coaxial to the axis of rotation of said barrel.

The barrel is rotatably driven by having one of said rollers associated with suitable power means. According to a specific form of embodiment of this invention, an aperture is formed through the upper base of the barrel for introducing the hides, or other materials to be processed, together with the liquid and/or pulverulent treatment products, and adjacent the edge of the lower base a drain cock is provided.

To prevent this drain cock from being clogged by hides, skins or other treated materials, a circular perforated partition is provided in the barrel parallel to, and at a short distance from, the lower base thereof.

Preferably, the cylindrical or lateral wall of revolution of the barrel comprises near said perforated partition an aperture provided with a detachable or hinged lid for discharging the hides therefrom.

Finally, the inner wall of revolution of the barrel carries all the elements necessary for assisting in properly carrying along and thoroughly mixing the hides. These elements may consist of radialpins or studs.

According to a modified form of embodiment of the barrel of this invention and in order to improve the operating conditions while improving the homogeneity of the treatment itself, at least that portion of the lateral wall of revolution of the barrel which extends between the swivel pivot and said annular ring has a frustoconical configuration with the major base coincident with or adjacent to said ring, the taper angle of the cone ranging preferably from to 30.

Advantageously, that portion of the lateral wall of revolution which extends beyond said ring is likewise of frustoconical configuration with its major base coinci- 2 dent with, or adjacent to, said ring, and its minor base provided with the loading aperture, the taper angle of this portion ranging from 30 to Preferably, the length of the frustoconical wall portion extending from said ring to said swivel pivot ranges from one-half to three fourths of the total length of the treatment barrel.

However, according to a specific form of embodiment of the treatment barrel of this invention the means provided for preventing the material being treated from clogging the drain cock consist of a frustoconical annulus of perforated sheet material secured to the inner wall so as to bridge the inner corner of the lower base of the barrel which carriers the drain cock. With this arrangement, due to the elimination of the sharp inner corner at the lower end of the barrel, the movement of the treated material is facilitated during the barrel rotation.

However, if the means provided for carrying along the material during the barrel rotation consists of radial pins or the like, these may in some cases prove detrimental to the material being processed in that they exert a rather coarse stirring action; moreover, in the case of a biconical wall, the pins of the rows disposed on either side of the ring converge by pair, thus constituting an undesired retaining means with respect to the treated material.

To this end, there is provided, according to a modified form of embodiment and as a substitute for, or in combination with, said radial pins, a plurality of longitudinal ribs extending from the lower base to the upper base of the barrel, and somewhat spaced from the inner cylindrical, tapered or biconical wall of the barrel, each rib having a rectilinear, bent or helical longitudinal profile or configuration.

An advantageous feature provided by these ribs is that the treated material is carried along without any risk of damaging same while preserving a convenient space between said ribs and the inner wall of revolution of the barrel for circulating the treatment liquid.

If these bars are used as substitutes for the aforesaid radial pins, the longitudinal profile of their edges directed radially towards the barrel axis comprises a plurality of radial projections or lobes.

Preferably, these longitudinal ribs are so disposed within the barrel that their side faces form a certain angle to the radial plane of the barrel containing the root edge of the lateral face considered, the angles of inclination of all the ribs having the same value and orientation.

With this arrangement it is possible, according to the selected direction of rotation of the barrel, to modify the mechanical action exerted on the hides as a function of the operating characteristics contemplated, notably as a function of the percentage of treatment liquid to the total weight of hides contained in the barrel.

In the foregoing it is stated that the angle of tilt of the axis of rotation of the barrel was subordinate to the specific nature of the treatment to be performed and also to the quality and nature of the treated hides. In the above-described simplified form of embodiment the angle of tilt of the axis of revolution of the barrel is determined initially through the difference in height between the supports of the roller shafts and the swivel bearing supporting the barrel.

However, according to a modification of this lastmentioned form of embodiment, the shafts of the rollers engaged by the ring surrounding the barrel are carried by the free ends of a yoke-shaped support of which the central arm carries the swivel bearing, a yoke being pivoted in turn about a horizontal shaft extending through its two lateral arms, means being provided for locking this pivotal mounting in any desired angular position of said yoke.

This arrangement is advantageous not only in that it permits the adjustment of the angle of tilt of the axis of revolution of the barrel but also in that it permits the discharge of the treated products through the loading aperture, since this aperture can be moved to allow position by simply tipping the barrel completely forwards, previous release of the locking means provided between the yoke and its support.

Preferably, the axis of the pivotal mounting of the yoke on its support is so positioned that it passes through the center of gravity in the barrel (in the filled condition of the latter) when the axis of revolution of the barrel is in its average angular position.

According to another possible form of embodiment of the treatment barrel of this invention, the ribs provided therein for carrying along the materials undergoing the treatment have a helical profile closely conforming the curvature of the inner wall of the barrel, and their faces inclined towards the lower bottom of the barrel carry rectilinear sections.

The combination of these helical and rectilinear ribs is advantageous in that in one direction of rotation of the barrel which corresponds to the normal treatment of the materials therein the rectilinear rib sections have a preponderant function, the materials being carried along as if the helical ribs were not present therein, that is, without producing any axial effect. On the other hand, when the barrel is rotated in the opposite direction, the function of the helical ribs becomes preponderant in turn and causes the treated materials to be forced towards, and discharged through, the aperture formed in the upper base of the barrel.

BRIEF DESCRIPTION OF THE DRAWINGS An understanding of the invention may be obtained from the foregoing and following description thereof, taken in conjunction with the appended drawings, in which:

FIGS. 1, 2 and 3 illustrate diagrammatically in side elevational views and fragmentary section three difierent forms of embodiment of the barrel according to this invention;

FIG. 4 is a cross section showing a modification brought to the barrel structure shown in FIG. 3;

FIG. 5 is a side elevational view showing another modified form of embodiment of this invention; and

FIG. 6 is a view similar to FIG. 3 showing a modified form of embodiment of the barrel illustrated in FIGS. 3 and 4.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The treatment barrel illustrated in FIG. 1 comprises a cylinder 2 of circular cross-sectional contour, closed at both ends by flat bottom shells or bases 3, 4 respectively.

This treatment barrel is adapted to be rotatably driven about its axis of revolution 5. To this end, its cylindrical wall of revolution 2 is surrounded in the vicinity of its bottom 3 by a ring or belt 6 through which the barrel bears on a pair of rollers 7 having their axes parallel to the barrel axis 5, only one of these rollers being visible in the drawing.

On the other hand, the other bottom 4 comprises a reinforcing plate 8 supporting coaxially a stub shaft 9 journaled in a swivel bearing 11.

The shafts of rollers 7 and of swivel bearing 11 are carried by supports 12 and 13, respectively, so disposed that the barrel axis 5 is tilted to the horizontal 14 and that the bottom 3 constitutes the upper bottom shell or base while the other bottom 4 constitutes the lower bottom shell or base of the barrel.

A circular aperture 15 is formed in the upper bottom 3 for introducing the hides or skins, and also the treatment products in liquid and/or pulverulent form.

Mounted at the edge of the lower bottom 4 is a drain cock or valve 16 for discharging the treatment liquids and powders at the end of the treatment.

A perforated diametral partition 17 is provided within the barrel, near the lower bottom 4, for preventing the hides or other materials from clogging the drain cock 16.

On the other hand, the cylindrical wall 2 is provided near the aforesaid perforated partition 17 with an aperture 18 for discharging the hides, this aperture being provided with a detachable or hinged lid 19.

Also preferably, the axis of this aperture 18 is preferably located in the same diametral plane of the barrel 2 as the drain cock 16, so that the hides can be discharged from the barrel immediately after draining the liquid and pulverulent products therefrom, without having to tilt the barrel therefor.

Finally, radial pins or studs 21 project from the inner face of the cylindrical wall 2 of the barrel in order to improve the stirring of the hides therein.

With this barrel, the stirring action exerted on the hides and treatment products introduced therein is considerably improved due to the inclination of the axis 5 to the horizontal, for the movement impressed to the hides as a consequence of the barrel rotation takes place in inclined planes differing therefore from the vertical planes in which gravity and buoyancy are relied upon.

For rotatably driving the barrel many known and suitable means may be contemplated; thus, for instance, a shaft 22 of roller 7 shown in the figure may be provided with an extension 22a rigid with a pulley 23 rotatably driven from a motor 24 through an endless transmission belt 20.

Instead of a cylindrical configuration as described hereinabove with reference to FIG. 1, a biconical or double frustoconical configuration as illustrated in FIG. 2 may be contemplated. In this modified form of embodiment the barrel 25 comprises two frustoconical sections 25a and 25b assembled at their major bases of same diameter, with the interposition of a short, beltforming cylindrical portion 6 enabling the barrel to bear on the supporting and driving rollers 7 without the interposition of a belt-forming ring, the rollers 7 (as in the preceding form of embodiment) having their axes parallel to the axis of revolution 5 of barrel 25; here again, only one roller 7 is visible in the figure.

Also as in the preceding example the axis 5 is inclined to the horizontal 14.

In addition to the rollers 7 engaged by said cylindrical portion 6 the barrel 25 bears on a swivel bearing 11 through a stub shaft 9 rigid with a reinforcing plate 8 A drain cock 16 is mounted near the edge of the lower bottom 4.

The major frustoconical section 25a (of which the minor base constitutes the bottom 4) is the longer sec tion of the barrel and has a taper angle 26 of a value ranging from about to about 30; of course the value of this taper angle depends on the nature of the materials to be treated in the barrel.

The length l of this frustoconical section 25a should range preferably from one-half to three fourths of the total length L of barrel 25.

The taper angle 27 of the smaller section 25b, of which the minor base constitutes the upper bottom 3 of barrel 25 and is consequently shorter, should range preferably from about 0 to about 90.

Preferably, the diameter d of the minor base of this shorter frustoconical section 25b corresponds to that of said loading aperture 15 and ranges preferably from one fourth to three fourths of the diameter D of cylindrical section 6.

Moreover, the length L of barrel 25 advantageously ranges from D to 2D.

Also advantageously the perforated inner partition provided in the barrel described with reference to FIG. 1 for isolating the drain cock 16 from the treated materials is replaced by a frustoconical annulus 28 of perforated sheet material, so that any risk of clogging the drain cock 16 with the treated materials is safely avoided while eliminating the blind corner formed between the lower bottom shell 4 and the frustoconical wall of revolution 25a, which might cause treatment products to accumulate therein and therefore impair the homogeneity of the treatment.

Of course, all the devices and means already contemplated in the case of the barrel shown in FIG. 1 may be adapted to the barrel of FIG. 2, such as notably the discharge aperture 18 formed in the frustoconical wall 25a adJacent the drain cock 16 and/or radial studs 21 projecting from the inner wall of. both frustoconical walls 25a and 25b of barrel 25, in order to improve the thorough stirring and mixing of the processed material and therefore the uniformity of the treatment.

In the modified form of embodiment illustrated in FIG. 3, as in the preceding one, the treatment barrel 25 has a biconical wall in that between the upper and lower bottom shells 3, 4 it comprises a long frustoconical section 25a and a short frustoconical section 25b assembled at their major bases with the interposition of a short race-forming cylindrical section 6.

This form of embodiment comprises similarly the supports 12 and 13 for the shafts 22 of roller 7 and for the bearing 11 of shaft 9, the barrel axis being also inclined to the horizontal 14; finally, as in the example of FIG. 2, the drain cock 16 is protected by a frustoconical corner grid 28, and a discharge aperture 19 is provided in the longer frustoconical wall 25a near said drain cock.

In addition, the barrel illustrated in HG. 3 comprises between the bottoms 3 and 4 lonw'tudinal ribs 29 shaped to conform to the longitudinal profile of the inner face of the wall of revolution and disposed adjacent this wall.

These ribs 29 may be disposed between rows of radial studs or pins 21 (shown in dash lines in the figure) so that these pins project slightly towards the barrel axis within the cylinder or squirrel cage formed by the ribs 29.

Alternatively, these pins or studs 21 may be replaced completely by the ribs 29.

Finally, according to a further modification, the inner edge of these ribs may be shaped to include inner radial projecnons or lobes 29a adapted to perform the same function as the pins 21.

The choice of the number of ribs 29, as well as their use in combination with or as a substitute for the pins 21, and the presence of projections 29a, depend essentially on the specific nature of the materials to be treated and of the treatment to be applied thereto.

Thus, for example, in the case of fragile materials, the ribs 29 are not rectilinear but preferably of helical configuration.

The barrel illustrated in FIG. 4 constitutes an advantageous modification of the one shown in FIG. 3. It comprises a long frustoconical section 25a formed with an integral bottom shell 4 and provided along its inner comer with a perforated grid 28 for protecting the drain cock (not shown) from a possible clogging by the hides and also for preventing material from accumulating in this corner.

As in the example illustrated in FIG. 3, the ribs 29 provided for carrying along the hides during the barrel rotation are secured to the inner wall of revolution of the barrel. However, as clearly shown in FIG. 4, in contrast to the structure illustrated in FIg. 3, each lateral face of the ribs 29 is inclined by an angle a to a radial plane 35 containing the root edge of said lateral face of a rib 29. Of course, the angles of inclination of all the ribs have the same value and the same orientation.

As a result of this arrangement the mechanical treatment applied to the hides during the process is not the same according as the barrel is rotated in the direction of arrow 36 or in the direction of arrow 37. Of course, when the barrel revolves in the direction of the arrow 36, the impulses exerted on the hides will be comparatively smooth since they will be applied through the trailing edges of ribs 29, and when the barrel revolves in the direction of the arrow 37 the action exerted by these ribs on the hides will be considerably stronger, since it will be applied through the leading edges of said bars 29.

Thus, two different treatment types may be applied with the same barrel, by simply providing means permitting of driving the barrel in either direction.

In the modified form of embodiment illustrated in FIG. 5, the treatment barrel is of the same general type as described hereinabove with reference to FIGS. 2, 3 and 4, in that it comprises between an upper bottom shell 3 and a lower bottom shell 4 a relatively long frustoconical wall section 25a and a relatively short frustoconical wall section 25b, these sections being assembled at their major bases with the interposition of a short race-forming cylindrical section 6.

A filling aperture 15 is formed in the upper bottom 3. According to a modification characterizing this specific form of embodiment the shafts 22 of rollers 7 engaged by the cylindrical race-forming section 6 are carried by the free ends of a yoke-shaped member 31, and the swivel bearing 11 supporting the shaft 9 coaxial to the axis of revolution 5 of barrel 25 is carried by the central arm of said yoke 31.

This yoke 31 is pivotally mounted in turn, through a pair of coaxial trunnions 32 each carried by and rigid with a lateral arm of said yoke, on a strap-shaped support 33.

As shown with this arrangement the angle of tilt of the axis of revolution 5 of barrel 25 to the horizontal 14 can be modified at will.

Of course, the angle of tilt may be adjusted manually I or through any known and suitable mechanical, electro-mechanical, pneumatic, hydraulic or other means.

Thus, the angle of tilt of the barrel axis 5 to the horizontal 14 may be set at any desired and suitable value, for example between and 50, in order to adapt the process conditions to particular and optimum treatment conditions and/or requirements.

Preferably, the position of trunnions 32 is such that when the barrel 25 has been filled the center of gravity of the barrel is coincident with their common axis.

In addition of this possibility of adjusting the tilt of axis 5, the pivotal mounting of yoke 31 of trunnions 32 is also convenient for tipping the barrel 25 in the direction of the arrow 34 so as to bring the filling aperture 15 to its lower or discharge position.

Under these conditions, the discharge aperture and lid 18, 19 of the preceding forms of embodiment may be dispensed with.

However, the drain cock 16 is still necessary as well as the protecting perforated sheet 28.

The example illustrated in FIG. 6 shows a modified form of embodiment of the structures shown in FIGS. 3 and 4 in case the inner ribs 29 have a helical profile and carry rectilinear longitudinal bar sections on their sides facing the lower bottom shell of the barrel.

In this example, the lateral wall of treatment barrel 25 is of cylindro-conical configuration; in other words, it comprises between the upper bottom shell 3 provided with the loading aperture 15 and the lower bottom shell 4 a relatively short frustoconical section 25b and a relatively long cylindrical section 25c, the major base of section 25b having the same diameter as said cylindrical section 250 and being assembled by this base to this last-named section, a race-forming outer ring 6 being provided adjacent this joint.

The cylindrical section 250 is rigid with the lower bottom 4, and a frustoconical grid 28 is fitted in the inner corner for protecting the drain cock 16 from possible clogging thereof by the hides or other products during the treatment, while eliminating a blind corner where materials could accumulate detrirnentally.

Between the bottom shells 3 and 4 a plurality of spaced helical ribs 38 closely accomodating the curvature of the inner wall of revolution of the barrel are disposed, as shown.

Moreover, rectilinear rib sections 39 shown in the drawing as being parallel to the generatrices of wall 25 are secured to the lateral sides of helical ribs 38 which are facing the lower bottom 4. Under these conditions these rectilinear sections 39 form in conjunction with helical ribs 38 an angle B complementary to the angle 7 which is the pitch angle of the helical ribs in relation to a plane perpendicular to the axis of barrel 25.

However, only the rectilinear rib sections 39 associated with one of the helical ribs 38 are shown in the figure in order to simplify the drawing.

In one direction of rotation, the hides or other products to be treated are carried along by the helical ribs 38 and in this case the hides or other products are urged towards the aperture 15 formed in the upper bottom shell 3 of the barrel.

When the barrel is rotated the other way, the elements 39 become preponderant, therefore without introducing an axial component, so that the hides or other products are treated efficiently.

To permit an efficient circulation of the treatment liquids and products, orifices 40, small enough to avoid any damage to the treated materials, may be formed if desired in the helical ribs 38.

Although the present invention has been described in conjunction with a plurality of preferred embodiments, it is to be understood that further modifications and variations may be resorted to without departing from the spirit and scope of the invention, as those skilled in the art will readily understand. Such modifications and variations are considered to be within the purview and scope of the invention and appended claims.

What I claim as new is:

1. A rotary barrel, preferably for the treatment of hides and skins, comprising a bottom shell, walls having a circular cross-sectional contour with a substantially cylindrical configuration and a top shell, with an axis of rotation of the barrel, coincident with its axis of revolution, being considerably inclined to the horizontal, namely several tens of degrees above the horizontal, means for adjusting the angle of tilt of said axis of rotation according to the nature of the treatment to be performed and the materials to be treated, an annular ring surrounding the cylindrical walls in the vicinity of said top shell, a pair of rollers engaging said annular ring at symmetrical locations below said axis of rotation, having their axes parallel to said axis of rotation so as to run on said annular ring like on a rolling race, a stub shaft in the center of said bottom shell, a swivel bearing coaxial to said axis of rotation for rotatably mounting said stub shaft therein, wherein one of said rollers is a driving roller for rotating the barrel in either direction, a yoke-shaped support having two side arms for carrying shafts of said rollers at their free ends, for rotatably supporting the barrel through said annular ring, a central arm for supporting said swivel bearing, a pair of coaxial trunnions, each of them being carried by and rigidly secured to one of said side arms at a distance from said free ends for pivotally mounting said yoke-shaped support, and means for locking the latter in any desired angular position.

2. The barrel as set forth in claim 1, wherein said top shell of the barrel has an aperture for introducing the materials to be treated as well as the treatment products in liquid and pulverulent form.

3. The barrel as set forth in claim 2, further comprising a drain cock fitted through said bottom shell near its edge.

4. The barrel as set forth in claim 3, further comprising a perforated partition disposed within the barrel, parallel to and in close vicinity of said bottom shell, to prevent said drain cock from being clogged by the hides or by other materials.

5. The barrel as set forth in claim 4, wherein said cylindrical walls are provided in the vicinity of said partition with an aperture for discharging the treated products 6. The barrel as set forth in claim 4, wherein said partition consists of a frustoconical ring of perforated sheet material which is secured to the inner corner of said lower bottom shell.

- 7. The barrel as set forth in claim 1, further comprising stirring means carried by the inner wall of the barrel, and means for carrying along the hides and skins, thus improving the thorough mixing thereof.

8. The barrel as set forth in claim 7, wherein said carrying means consists of pins extending radially inwards from the inner wall surface of the barrel.

9. The barrel as set forth in claim 7, wherein said carrying means consist of longitudinal ribs provided between said top and said bottom shells, in close vicinity of said cylindrical walls.

10. The barrel as set forth in claim 9, wherein said ribs have a rectilinear profile.

11. The barrel as set forth in claim 9, wherein said ribs have a bent profile.

12. The barrel as set forth in claim 9, wherein said ribs have a helical profile.

13. The barrel as set forth in claim 12, wherein said ribs have a profile closely conforming to the contour of the inner face of the barrel wall, each rib carrying on its side facing said bottom shell at least one rectilinear section parallel to said axis a rotation.

14. The barrel as set forth in claim 9, wherein said ribs carry internal radial projections. 1

15. The barrel as set forth in claim 9, wherein said ribs are so arranged within the barrel that the planes of their side faces are at an angle with the radial plane of the barrel which contains the root edge of said side face, the angle of inclination of all ribs having the same value and orientation.

16. The barrel as set forth in claim 1, wherein at least one portion of the wall of the barrel, which extends between said pivot axis and said annular ring, has a frustoconical configuration, with its major base adjacent to said ring and a taper angle of 0 to 30.

17. The barrel as set forth in claim 16, wherein a portion of said wall which extends beyond said annular ring is also of frustoconical configuration, with said major base connected to said annular ring and the minor base provided with a loading aperture, the taper angle between said bases ranging from 30 to 18. The barrel asset forth in claim 17, wherein the diameter of said minor base of the shortest frustoconical wall portion, which diameter corresponds to that of said loading aperture, ranges from one fourth to three fourths of the diameter of said annular ring engaged by said rollers. 

1. A rotary barrel, preferably for the treatment of hides and skins, comprising a bottom shell, walls having a circular crosssectional contour with a substantially cylindrical configuration and a top shell, with an axis of rotation of the barrel, coincident with its axis of revolution, being considerably inclined to the horizontal, namely several tens of degrees above the horizontal, means for adjusting the angle of tilt of said axis of rotation according to the nature of the treatment to be performed and the materials to be treated, an annular ring surrounding the cylindrical walls in the vicinity of said top shell, a pair of rollers engaging said annular ring at symmetrical locations below said axis of rotation, having their axes parallel to said axis of rotation so as to run on said annular ring like on a rolling race, a stub shaft in the center of said bottom shell, a swivel bearing coaxial to said axis of rotation for rotatably mounting said stub shaft therein, wherein one of said rollers is a driving roller for rotating the barrel in either direction, a yoke-shaped support having two side arms for carrying shafts of sAid rollers at their free ends, for rotatably supporting the barrel through said annular ring, a central arm for supporting said swivel bearing, a pair of coaxial trunnions, each of them being carried by and rigidly secured to one of said side arms at a distance from said free ends for pivotally mounting said yoke-shaped support, and means for locking the latter in any desired angular position.
 2. The barrel as set forth in claim 1, wherein said top shell of the barrel has an aperture for introducing the materials to be treated as well as the treatment products in liquid and pulverulent form.
 3. The barrel as set forth in claim 2, further comprising a drain cock fitted through said bottom shell near its edge.
 4. The barrel as set forth in claim 3, further comprising a perforated partition disposed within the barrel, parallel to and in close vicinity of said bottom shell, to prevent said drain cock from being clogged by the hides or by other materials.
 5. The barrel as set forth in claim 4, wherein said cylindrical walls are provided in the vicinity of said partition with an aperture for discharging the treated products.
 6. The barrel as set forth in claim 4, wherein said partition consists of a frustoconical ring of perforated sheet material which is secured to the inner corner of said lower bottom shell.
 7. The barrel as set forth in claim 1, further comprising stirring means carried by the inner wall of the barrel, and means for carrying along the hides and skins, thus improving the thorough mixing thereof.
 8. The barrel as set forth in claim 7, wherein said carrying means consist of pins extending radially inwards from the inner wall surface of the barrel.
 9. The barrel as set forth in claim 7, wherein said carrying means consist of longitudinal ribs provided between said top and said bottom shells, in close vicinity of said cylindrical walls.
 10. The barrel as set forth in claim 9, wherein said ribs have a rectilinear profile.
 11. The barrel as set forth in claim 9, wherein said ribs have a bent profile.
 12. The barrel as set forth in claim 9, wherein said ribs have a helical profile.
 13. The barrel as set forth in claim 12, wherein said ribs have a profile closely conforming to the contour of the inner face of the barrel wall, each rib carrying on its side facing said bottom shell at least one rectilinear section parallel to said axis of rotation.
 14. The barrel as set forth in claim 9, wherein said ribs carry internal radial projections.
 15. The barrel as set forth in claim 9, wherein said ribs are so arranged within the barrel that the planes of their side faces are at an angle with the radial plane of the barrel which contains the root edge of said side face, the angle of inclination of all ribs having the same value and orientation.
 16. The barrel as set forth in claim 1, wherein at least one portion of the wall of the barrel, which extends between said pivot axis and said annular ring, has a frustoconical configuration, with its major base adjacent to said ring and a taper angle of 0 to 30* .
 17. The barrel as set forth in claim 16, wherein a portion of said wall which extends beyond said annular ring is also of frustoconical configuration, with said major base connected to said annular ring and the minor base provided with a loading aperture, the taper angle between said bases ranging from 30* to 90* .
 18. The barrel as set forth in claim 17, wherein the diameter of said minor base of the shortest frustoconical wall portion, which diameter corresponds to that of said loading aperture, ranges from one fourth to three fourths of the diameter of said annular ring engaged by said rollers. 